1. Field of the Invention
This invention relates to a sliding roof device for a motor vehicle roof with a movable cover for selectively closing or at least partially exposing a roof opening in the motor vehicle roof, which can be raised into a ventilation position at its rear edge, and which has a sliding headliner movably located underneath the cover, the headliner, when positioned under the raised cover, is raised at its rear section for producing a ventilation gap and is kept in this raised position.
2. Description of Related Art
U.S. Pat. No. 6,309,013 discloses a motor vehicle roof with a roof opening and a sliding roof device in which the sliding headliner is connected to the cover by a catch means and held on it in its folded-up position. If the catch means has a high locking force in order to hold the sliding headliner securely on the cover, manual actuation is made difficult. On the other hand, if a low locking force is utilized, the sliding headliner can be separated from the cover and drop down.
A primary object of the present invention is to improve the initially mentioned sliding roof device with a sliding headliner such that the sliding headliner is securely held in its folded-up position and actuation of the sliding headliner is still possible without a major expenditure of force.
This object is achieved in accordance with the invention in a sliding roof device of the initially mentioned type sliding roof device in the provision of a lifting means which engages the rear section of the sliding headliner with a lifting force which pretensions the rear section into its folded-up position. While the rear section is being moved by a guide or adjustment means into the folded-up position, the lifting force provides for the rear section to be kept pretensioned along its guide means or adjustment means in the direction of its motion. The lifting force of the lifting means is directed such that at least one component of the lifting force acts in the direction along the guide for the rear section.
In one preferred embodiment, the lifting means has an increased or maximum lifting force with the rear section folded up, and it has a reduced or minimum lifting force with the rear section folded back into the displacement plane of the sliding headliner. In this way, the restoration force of the deformed material of the sliding headliner, which increases when folding up, can be counteracted. On the other hand, in the flat, folded-down arrangement, the frictional resistance is kept low by the minimum force which acts perpendicular to the guide so that the actuation resistance is not increased when the sliding headliner is moved.
If the lifting means is designed such that the lifting force increases continuously when the rear section of the sliding headliner is folded up, the manual displacement of the sliding headliner is facilitated and the end position is continuously approached without the increased catch resistance of a continuous catch means having to be overcome and without catch noise occurring.
One possible embodiment of the guide for the rear section calls for the rear section of the sliding headliner to be guided on an upwardly curved or pivoted guideway into its folded-up position. Transitions or coupling processes are avoided by the continuous guideway. The front section of the sliding headliner can be guided on the guideway in the displacement plane.
Preferably, the lifting means connects the front section and the rear section of the sliding headliner on the top side, and in one simple configuration, applies the lifting force to the rear section by a spring means and especially by means of a tension spring.
In one alternative embodiment, the lifting means has a lever means with a front lever and a rear lever which are pivotally coupled, on the one hand, to the front section and the rear section of the sliding headliner, respectively, and on the other hand, are pivotally connected to one another on a hinge axle, the spring means or the tension spring connecting the rear lever or the hinge axis to the front section. Here, different configurations are possible which increase the spring force which acts as the lifting force when the rear section is folded up.
Embodiments of the sliding roof device are explained in detail below with reference to the accompanying drawings.